SOLUTION: I have tried this problem for hours now and I still have no idea how to solve it can you help?
- Assume cos Ө = -1/3. Use trig identities to find the exact value of ear expr
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-> SOLUTION: I have tried this problem for hours now and I still have no idea how to solve it can you help?
- Assume cos Ө = -1/3. Use trig identities to find the exact value of ear expr
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Question 770439: I have tried this problem for hours now and I still have no idea how to solve it can you help?
- Assume cos Ө = -1/3. Use trig identities to find the exact value of ear expression.
a) cos(-Ө) - cos(Ө-4pi) + cos(Ө +2pi) Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! - Assume cos Ө = -1/3. Use trig identities to find the exact value of ear expression.
a) cos(-Ө) - cos(Ө-4pi) + cos(Ө +2pi)
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cos(- Ө)=cos( Ө)=-1/3 (cos is an even function)
cos(Ө-4pi)=cos Ө*cos4π+sin Ө*sin4π=cos Ө*1+sin Ө*0=cos Ө=-1/3
cos(Ө+2pi)=cos Ө*cos2π-sin Ө*sin2π=cos Ө*1-sin Ө*0=cos Ө=-1/3
a) cos(-Ө) - cos(Ө-4pi) + cos(Ө +2pi)
=-1/3-(-1/3)+(-1/3)
=-1/3+1/3-1/3
=-1/3
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